de.caff.io.json

Class SimpleJsonWriter

java.lang.Object

de.caff.io.json.SimpleJsonWriter

All Implemented Interfaces:

java.io.Closeable, java.lang.AutoCloseable

public class SimpleJsonWriter
extends java.lang.Object
implements java.io.Closeable

Simple JSON writer.

Since:

2022/04/22

Author:

Rammi

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
(package private) static class	SimpleJsonWriter.State Internal state.

Constructor Summary

Constructors

Constructor and Description
SimpleJsonWriter(StringCollector stringCollector) Constructor.
SimpleJsonWriter(StringCollector stringCollector, int basicIndent) Constructor.
SimpleJsonWriter(StringCollector stringCollector, int basicIndent, boolean relaxed) Constructor.

Method Summary

Modifier and Type	Method and Description
SimpleJsonWriter	array(boolean... flags) Convenience method for outputting a whole array of boolean flags.
SimpleJsonWriter	array(double... numbers) Convenience method for outputting a whole array of double values.
SimpleJsonWriter	array(int... numbers) Convenience method for outputting a whole array of integers.
SimpleJsonWriter	array(java.lang.Iterable<java.lang.String> elements) Convenience method for outputting a whole array of strings.
SimpleJsonWriter	array(PrimitiveBooleanIterable flags) Convenience method for outputting a whole array of boolean flags.
SimpleJsonWriter	array(PrimitiveDoubleIterable numbers) Convenience method for outputting a whole array of double values.
SimpleJsonWriter	array(PrimitiveIntIterable numbers) Convenience method for outputting a whole array of integers.
SimpleJsonWriter	array(java.lang.String... elements) Convenience method for outputting a whole array of strings.
SimpleJsonWriter	beginArray() Start outputting a JSON array.
SimpleJsonWriter	beginObject() Start outputting a JSON object.
<T> SimpleJsonWriter	booleanArray(java.lang.Iterable<T> elements, java.util.function.Predicate<? super T> boolMapping) Convenience method for outputting a whole array of boolean flags created from general elements.
void	close() Close this writer.
SimpleJsonWriter	doubleArray(java.lang.Iterable<? extends java.lang.Number> numbers) Convenience method for outputting a whole array of numbers as double values.
<T> SimpleJsonWriter	doubleArray(java.lang.Iterable<T> elements, java.util.function.ToDoubleFunction<? super T> doubleMapping) Convenience method for outputting a whole array of double values created from general elements.
SimpleJsonWriter	endArray() End outputting a JSON array.
SimpleJsonWriter	endObject() End outputting a JSON object.
SimpleJsonWriter	intArray(java.lang.Iterable<? extends java.lang.Number> numbers) Convenience method for outputting a whole array of numbers as integers.
<T> SimpleJsonWriter	intArray(java.lang.Iterable<T> elements, java.util.function.ToIntFunction<? super T> intMapping) Convenience method for outputting a whole array of integers created from general elements.
SimpleJsonWriter	key(java.lang.String key) Output the key of a key-value pair.
static void	main(java.lang.String[] args) Test code
SimpleJsonWriter	nul() Output a null value.
<T> SimpleJsonWriter	stringArray(java.lang.Iterable<T> elements, java.util.function.Function<? super T,java.lang.String> toStringFunction) Convenience method for outputting a whole array of strings created from general elements.
SimpleJsonWriter	value(boolean value) Output a boolean value.
SimpleJsonWriter	value(double value) Output a double value.
SimpleJsonWriter	value(int value) Output an integer value.
SimpleJsonWriter	value(java.lang.String value) Output a string value.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

SimpleJsonWriter

public SimpleJsonWriter(@NotNull
                        StringCollector stringCollector)

Constructor. This writes without any superfluous white space.

Parameters:

stringCollector - string collector to write to

SimpleJsonWriter

public SimpleJsonWriter(@NotNull
                        StringCollector stringCollector,
                        int basicIndent)

Constructor.

Parameters:

stringCollector - string collector to write to

basicIndent - basic indentation, use -1 for optimal compactness w/o newlines, 0 for no indentation but newlines, or greater for newlines and indentation

SimpleJsonWriter

public SimpleJsonWriter(@NotNull
                        StringCollector stringCollector,
                        int basicIndent,
                        boolean relaxed)

Constructor.

Parameters:

stringCollector - string collector to write to

basicIndent - basic indentation, use -1 for optimal compactness w/o newlines, 0 for no indentation but newlines, or greater for newlines and indentation

relaxed - by default the writer expects to be started with a value, object, or array. If this parameter is true a key is also allowed.

Method Detail

key

@NotNull
public SimpleJsonWriter key(@NotNull
                                     java.lang.String key)

Output the key of a key-value pair.

Parameters:

key - key to add

Returns:

JSON writer for chaining

Throws:

java.lang.IllegalStateException - if adding a key is currently not allowed

value

@NotNull
public SimpleJsonWriter value(@Nullable
                                       java.lang.String value)

Output a string value.

A string value can appear after a key as part of a key-value pair, inside an array, or as single element.

Parameters:

value - string value

Returns:

JSON writer for chaining

Throws:

java.lang.IllegalStateException - if adding a value is currently not allowed

value

@NotNull
public SimpleJsonWriter value(int value)

Output an integer value.

A numeric value can appear after a key as part of a key-value pair, inside an array, or as single element. Please note that all numeric values in JSON are forwarded to 64bit double values, so this method is only for convenience.

Parameters:

value - integer value

Returns:

JSON writer for chaining

Throws:

java.lang.IllegalStateException - if adding a value is currently not allowed

value

@NotNull
public SimpleJsonWriter value(double value)

Output a double value.

A numeric value can appear after a key as part of a key-value pair, inside an array, or as single element. Please note that all numeric values in JSON are forwarded to 64bit double values, so if you call this with a long argument you might not be able to reread this value correctly.

Parameters:

value - double value

Returns:

JSON writer for chaining

Throws:

java.lang.IllegalStateException - if adding a value is currently not allowed

value

@NotNull
public SimpleJsonWriter value(boolean value)

Output a boolean value.

A boolean value can appear after a key as part of a key-value pair, inside an array, or as single element if this is enabled for this writer.

Parameters:

value - boolean value

Returns:

JSON writer for chaining

Throws:

java.lang.IllegalStateException - if adding a value is currently not allowed

nul

@NotNull
public SimpleJsonWriter nul()

Output a null value.

A null value can appear after a key as part of a key-value pair, inside an array, or as single element.

Returns:

JSON writer for chaining

Throws:

java.lang.IllegalStateException - if adding a value is currently not allowed

beginObject

@NotNull
public SimpleJsonWriter beginObject()

Start outputting a JSON object.

An object can appear as value of a key-value pair, as element of an array, or as root element.

Returns:

JSON writer for chaining

Throws:

java.lang.IllegalStateException - if adding an object is currently not allowed

endObject

@NotNull
public SimpleJsonWriter endObject()

End outputting a JSON object.

This will close the currently outputted object, and is only allowed at places where a key is also allowed.

Returns:

JSON writer for chaining

Throws:

java.lang.IllegalStateException - if no object is open, if this is called inside an array, or when the value of a key-value pair is not yet outputted

beginArray

@NotNull
public SimpleJsonWriter beginArray()

Start outputting a JSON array.

An array can appear as value of a key-value pair, as element of an array, or as root element.

Returns:

JSON writer for chaining

Throws:

java.lang.IllegalStateException - if adding an object is currently not allowed

endArray

@NotNull
public SimpleJsonWriter endArray()

End outputting a JSON array.

This will close the currently outputted array, and is only if currently inside an array.

Returns:

JSON writer for chaining

Throws:

java.lang.IllegalStateException - if no array is open, or if this is called inside an object

array

@NotNull
public SimpleJsonWriter array(@NotNull
                                       java.lang.String... elements)

Convenience method for outputting a whole array of strings.

Parameters:

elements - string elements

Returns:

JSON writer for chaining

Throws:

java.lang.IllegalStateException - if adding an array is not allowed

array

@NotNull
public SimpleJsonWriter array(@NotNull
                                       java.lang.Iterable<java.lang.String> elements)

Convenience method for outputting a whole array of strings.

Parameters:

elements - string elements

Returns:

JSON writer for chaining

Throws:

java.lang.IllegalStateException - if adding an array is not allowed

stringArray

@NotNull
public <T> SimpleJsonWriter stringArray(@NotNull
                                                 java.lang.Iterable<T> elements,
                                                 @NotNull
                                                 java.util.function.Function<? super T,java.lang.String> toStringFunction)

Convenience method for outputting a whole array of strings created from general elements.

Type Parameters:

T - element type

Parameters:

elements - general elements

toStringFunction - function which creates strings from the elements

Returns:

JSON writer for chaining

Throws:

java.lang.IllegalStateException - if adding an array is not allowed

array

@NotNull
public SimpleJsonWriter array(@NotNull
                                       int... numbers)

Convenience method for outputting a whole array of integers.

Parameters:

numbers - int elements

Returns:

JSON writer for chaining

Throws:

java.lang.IllegalStateException - if adding an array is not allowed

array

@NotNull
public SimpleJsonWriter array(@NotNull
                                       PrimitiveIntIterable numbers)

Convenience method for outputting a whole array of integers.

Parameters:

numbers - int elements

Returns:

JSON writer for chaining

Throws:

java.lang.IllegalStateException - if adding an array is not allowed

intArray

@NotNull
public SimpleJsonWriter intArray(@NotNull
                                          java.lang.Iterable<? extends java.lang.Number> numbers)

Convenience method for outputting a whole array of numbers as integers.

Parameters:

numbers - number elements

Returns:

JSON writer for chaining

Throws:

java.lang.IllegalStateException - if adding an array is not allowed

intArray

@NotNull
public <T> SimpleJsonWriter intArray(@NotNull
                                              java.lang.Iterable<T> elements,
                                              @NotNull
                                              java.util.function.ToIntFunction<? super T> intMapping)

Convenience method for outputting a whole array of integers created from general elements.

Type Parameters:

T - element type

Parameters:

elements - general elements

intMapping - function which creates integers from the elements

Returns:

JSON writer for chaining

Throws:

java.lang.IllegalStateException - if adding an array is not allowed

array

@NotNull
public SimpleJsonWriter array(@NotNull
                                       double... numbers)

Convenience method for outputting a whole array of double values.

Parameters:

numbers - double elements

Returns:

JSON writer for chaining

Throws:

java.lang.IllegalStateException - if adding an array is not allowed

array

@NotNull
public SimpleJsonWriter array(@NotNull
                                       PrimitiveDoubleIterable numbers)

Convenience method for outputting a whole array of double values.

Parameters:

numbers - double elements

Returns:

JSON writer for chaining

Throws:

java.lang.IllegalStateException - if adding an array is not allowed

doubleArray

@NotNull
public SimpleJsonWriter doubleArray(@NotNull
                                             java.lang.Iterable<? extends java.lang.Number> numbers)

Convenience method for outputting a whole array of numbers as double values.

Parameters:

numbers - number elements

Returns:

JSON writer for chaining

Throws:

java.lang.IllegalStateException - if adding an array is not allowed

doubleArray

@NotNull
public <T> SimpleJsonWriter doubleArray(@NotNull
                                                 java.lang.Iterable<T> elements,
                                                 @NotNull
                                                 java.util.function.ToDoubleFunction<? super T> doubleMapping)

Convenience method for outputting a whole array of double values created from general elements.

Type Parameters:

T - element type

Parameters:

elements - general elements

doubleMapping - function which creates doubles from the elements

Returns:

JSON writer for chaining

Throws:

java.lang.IllegalStateException - if adding an array is not allowed

array

@NotNull
public SimpleJsonWriter array(@NotNull
                                       boolean... flags)

Convenience method for outputting a whole array of boolean flags.

Parameters:

flags - boolean elements

Returns:

JSON writer for chaining

Throws:

java.lang.IllegalStateException - if adding an array is not allowed

array

@NotNull
public SimpleJsonWriter array(@NotNull
                                       PrimitiveBooleanIterable flags)

Convenience method for outputting a whole array of boolean flags.

Parameters:

flags - boolean elements

Returns:

JSON writer for chaining

Throws:

java.lang.IllegalStateException - if adding an array is not allowed

booleanArray

@NotNull
public <T> SimpleJsonWriter booleanArray(@NotNull
                                                  java.lang.Iterable<T> elements,
                                                  @NotNull
                                                  java.util.function.Predicate<? super T> boolMapping)

Convenience method for outputting a whole array of boolean flags created from general elements.

Type Parameters:

T - element type

Parameters:

elements - general elements

boolMapping - function which creates booleans from the elements

Returns:

JSON writer for chaining

Throws:

java.lang.IllegalStateException - if adding an array is not allowed

close

public void close()

Close this writer.

Specified by:

close in interface java.io.Closeable

Specified by:

close in interface java.lang.AutoCloseable

main

public static void main(java.lang.String[] args)
                 throws java.io.IOException

Test code

Parameters:

args - ignored

Throws:

java.io.IOException - when writing fails